NEW ZEALAND GLULAM SPAN TABLES

Transcription

1 NEW ZEALAND GLULAM SPAN TABLES The Glulam Span Tables have been developed primarily for domestic applications in accordance with NZS3603 Timber Structures Standard and with the joint AS/NZS 1328:1998 standard Glue Laminated Structural Timbers The purpose of these tables is to make it easier for builders, draughtsmen, architects and engineers to come up with a quick and accurate design for Glulam beams. These cover the most common domestic uses for Glulam beams roof beams, rafters, ridges, lintels and floor beams. At a glance designers and builders will be able to find the correct size of beams for a variety of spans at various spacings and loadings. Published New Zealand Pine Manufacturers Association 2008 Acknowledgement: Appreciation is extended to McIntosh Timber Laminates Ltd, Timberbond Industries (NZ) Ltd and Hunters (1998) Ltd for their assistance in the development of these tables. NZ Pine Manufacturers Association P.O. Box 3551 Richmond, Nelson (03) (03) info@pine.net.nz Page 1

2 STRUCTURAL CERTIFICATION : PRODUCER STATEMENT Producer Statement Glulam Span Tables The span tables and details in this brochure for glue laminated beams (Glulam) have been designed in accordance with sound and widely accepted engineering principles. The calculation and computation of these span tables was undertaken by Holmes Consulting Group Structural and Civil Engineers. The design properties of glue laminated timber in this brochure were determined in accordance with clauses 2.2 and C2.3 of NZS 3603: Timber Structures Standard. Laminated timber is a product certified by the Standards of New Zealand as being manufactured in accordance with the joint New Zealand/Australian Standard AS / NZS 1328:1998. Product should be obtained from manufacturers holding a current licence under the inspection scheme administered by the NZ Timber certification Board. The list of manufacturers licensed to AS/NZS Glue Laminated Structural Timbers is tabled on page 71 of this publication. Under this system all manufacturers are certified by the New Zealand Timber Certification Board, audited six-monthly and independently assessed and issued a licence number by Bureau Veritas. This process entitles approved manufacturers to display the S mark on all product. Product Liability for any loss incurred through non-performance would rest with the licenced manufacturer and the certifying authority. Structural design is in agreement with NZS 3603 (verification method B1 / VM1, 6.1 and NZS 4203 (Verification method B1 / VM1,2.2) with loads and deflection criteria as indicated on the tables. Seviceability and other criteria were selected using NZS 4203 (Verification method B1 / VM1,2.2), (Acceptable solution B1 / AS1,4.1). When installed in accordance with the specifications, details and limitations in this brochure, glue laminated timber members will comply with the requirements of the New Zealand Building Code. Disclaimer: While very effort has been made and all reasonable care taken to ensure the accuracy of the material contained herein, the Authors, Editors and Publishers of this Publication shall not be held to be liable or responsible in any way whatsoever and expressly disclaim any liability or responsibility for any loss damage costs or expenses howsoever incurred by any person whether the purchaser of this work or otherwise including but without in any way limiting any loss or damage costs or expenses incurred as a result of or in connection with the reliance whether whole or partial by any person as aforesaid upon any part of the contents of this publication. Should expert assistance be required, the services of a competent professional person should be sought Bruce Black National Manager Holmes Consulting Group The list of manufacturers licensed to AS/NZS Glue Laminated Structural Timbers is tabled on page 71 of this document. Under this system all manufacturers are certified by the New Zealand Timber Certification Board, audited six-monthly and independently assessed and issued a licence number by Bureau Veritas. This process entitles approved manufacturers to display the S mark on all product. Page 2

3 TABLE OF CONTENTS STRUCTURAL CERTIFICATION : PRODUCER STATEMENT... 2 INTRODUCTION SPECIFICATION DETAILS n STRUCTURAL GRADES... 6 n APPEARANCE GRADES... 6 n SERVICE CLASSES... 7 n TIMBER TREATMENT SPECIFICATION OPTIONS... 7 n PAINTING PROCEDURE... 7 ENGINEERING DESIGN PROPERTIES n BEAMS FULLY RESTRAINED ON COMPRESSION FLANGE GL n BEAMS FULLY RESTRAINED ON COMPRESSION FLANGE GL n BEAMS FULLY RESTRAINED ALONG TENSION FLANGE GL n BEAMS FULLY RESTRAINED ALONG TENSION FLANGE GL GLULAM SPAN TABLES n FLOOR BEAMS 1.5 kpa LIVE LOAD GL n FLOOR BEAMS 1.5 kpa LIVE LOAD GL n FLOOR BEAMS 2.0 kpa LIVE LOAD GL n FLOOR BEAMS 2.0 kpa LIVE LOAD GL n FLOOR BEAMS 3.0 kpa LIVE LOAD GL n FLOOR BEAMS 3.0 kpa LIVE LOAD GL n ROOF BEAMS - 3.0kPa LIVE LOAD GL n ROOF BEAMS, RAFTERS & RIDGES LIGHT ROOF n ROOF BEAMS, RAFTERS & RIDGES LIGHT ROOF MEDIUM WIND SPEED GL n ROOF BEAMS, RAFTERS & RIDGES LIGHT ROOF HIGH WIND SPEED GL n ROOF BEAMS, RAFTERS & RIDGES LIGHT ROOF - MEDIUM WIND SPEED GL n ROOF BEAMS, RAFTERS & RIDGES LIGHT ROOF HIGH WIND SPEED GL n ROOF BEAMS, RAFTERS & RIDGES HEAVY ROOF MEDIUM WIND SPEED GL n ROOF BEAMS, RAFTERS & RIDGES HEAVY ROOF - HIGH WIND SPEED GL n ROOF BEAMS, RAFTERS & RIDGES HEAVY ROOF MEDIUM WIND SPEED GL n ROOF BEAMS, RAFTERS & RIDGES HEAVY ROOF HIGH WIND SPEED GL n LINTELS SUPPORTING LIGHT ROOF & 1.5 kpa FLOOR GL n LINTELS SUPPORTING LIGHT ROOF & 1.5 kpa FLOOR GL n LINTELS SUPPORTING HEAVY ROOF & 1.5 kpa FLOOR GL n LINTELS SUPPORTING HEAVY ROOF & 1.5 kpa FLOOR GL n LINTELS SUPPORTING LIGHT ROOF & 2.0 kpa FLOOR GL n LINTELS SUPPORTING LIGHT ROOF & 2.0 kpa FLOOR GL n LINTELS SUPPORTING HEAVY ROOF & 2.0 kpa FLOOR GL n LINTELS SUPPORTING HEAVY ROOF & 2.0 kpa FLOOR GL n LINTELS SUPPORTING LIGHT ROOF & 3.0 kpa FLOOR GL n LINTELS SUPPORTING LIGHT ROOF & 3.0 kpa FLOOR GL n LINTELS SUPPORTING HEAVY ROOF & 3.0 kpa FLOOR GL n LINTELS SUPPORTING HEAVY ROOF & 3.0 kpa FLOOR GL n LINTELS SUPPORTING ROOF ONLY (LIGHT ROOF) GL n LINTELS SUPPORTING ROOF ONLY (LIGHT ROOF) GL n LINTELS SUPPORTING ROOF ONLY (HEAVY ROOF) GL n LINTELS SUPPORTING ROOF ONLY (HEAVY ROOF) GL n ROOF HIP MEMBERS GL n ROOF HIP MEMBERS GL n ROOF HIP MEMBERS PRECAMBERED BEAMS GL n ROOF HIP MEMBERS PRECAMBERED BEAMS GL n AUSTRALIAN STRUCTURAL LAMINATED BEAMS LIGHT ROOF GL n AUSTRALIAN STRUCTURAL LAMINATED BEAMS HEAVY ROOF GL QUESTION & ANSWERS MEMBERS LICENSED BY BUREAU VERITAS TO MANUFACTURE GLULAM Page 3

4 INTRODUCTION Glued laminated timber or Glulam is a strong, engineered, structural product, well proven in New Zealand building and construction for over 40 years and internationally for much longer. It was first used in 1893 to construct an auditorium in Basel, Switzerland. Now Glulam is gaining renewed popularity because of its many benefits to the designer, builder and end user. Ongoing research ensures that Glulam is designed to work better than ever in a host of construction applications. Increased design values have expanded design capabilities and improved performance. The new Bureau Veritas administered quality standards are internationally recognised and more performance based. This gives even greater assurance of long-term serviceability and performance meeting design. There are many reasons for using Glulam for your project from versatility to environmental reasons, to cost effectiveness. Unmatched versatility. Glulam has greater strength, stability and stiffness than dimensional timber and can be produced in uniform or varying depths to give strength where it is required. Lengths, dimensions and shapes can be produced almost without limit, making Glulam unsurpassed in its versatility. Appearance, aesthetics. Glue-laminated structural timber products are usually specified for the beauty as well as for strength. The natural aesthetic qualities of Glulam allow the structural elements of a building to be exposed for architectural effect. This combined with the natural warmth and timeless appeal of exposed timber make Glulam ideal for any application requiring an appealing and architecturally interesting structure. Lightweight. Weight for strength, a Glulam beam is stronger than both steel and concrete. This means that The solution for large open spaces is found in the strength and simplicity of Glulam roof frames. Three-story post and beam structure creates a unique feature demonstrating timber s natural strength and design possibilities. Glulam beams can span very long distances with minimal intermediate support required. Dependent upon specific loading conditions a steel beam may be 20% heavier and a reinforced concrete beam 600% heavier than an equivalent Glulam beam for carrying the same load. The resulting lighter structure can lead to significant economies in foundation construction. Consistency of Performance. The process of glue laminating timber eliminates the natural performance variations that characterise solid sawn timber. As Glulam beams are engineered wood products that are manufactured to meet specific performance criteria, the specifier and user can be assured that Glulam products will consistently perform as expected. Ease of installation. When it comes to installation existing, traditional skills can be used and builders who are confident in working with timber easily handle Glulam products. Other sub trades find timber easier and quicker to connect to. As a consequence, erection times are significantly reduced in Glulam structures. Environment. Glulam uses the World s most prolific renewable construction material. In Canada and New Zealand (where Pinus Radiata grows fastest), trees are growing faster than they are being consumed to build houses and the available plantation pine is increasing dramatically. For their load carrying capability, Glulam beams are very efficient to produce. The energy required to produce a glue-laminated beam from the log is only a fraction of the energy required to produce steel from ore or concrete from limestone. Using Glulam in fact contributes to a positive storage of carbon compared to the large amount of carbon emission resulting from the production of steel. All round, the production of Glulam has the least effect on the environment by far. Page 4

5 INTRODUCTION Fire resistance. When exposed to the heat of a fire, timber undergoes a thermal breakdown (pyrolysis) into combustible gases, and a layer of charcoal forms on the burning surface. Glue laminated timber burns slowly and at a predictable rate, and as such fire design techniques can be relatively easily applied. When large cross-sections are subjected to a fire a char forms around the outside of the beam that protects the core by restricting the oxygen supply. There have been examples of portal frame buildings that have effectively burnt down leaving only the charred portal frame. The portal frames were then cleaned and, after engineers inspection, the structure rebuilt on the existing Glulam. Harsh environments. Timber is naturally resilient to attack by corrosive atmospheres that would normally cause rust. With appropriate treatment Glulam members will completely avoid deterioration and require minimal long-term maintenance. This makes Glulam structural members suited to environments exposed to corrosive or highhumidity atmospheres. Pre-cambering. Often deflection is a controlling restraint in structural beam design, especially in longer spans. Whilst any structural member can be designed to minimise deflection, Glulam is the only engineered wood product that can easily be precambered to eliminate the aesthetic effect of in-service deflections. Curved Glulam portals highlight the design flexibility and natural beauty timber can bring in an indoor outdoor situation. Shock Resistance. Wood, steel, and concrete are the three principal materials utilised by civil engineers when designing structures. Unlike steel and concrete, which are cast and formed, wood is anisotropic by nature meaning it performs differently in different directions. Wood also has excellent thermal, acoustic and electrical insulating properties. These factors make it very resilient, naturally. This resilience is a great advantage and permits it to absorb seismic and wind shocks that would actually cause failure in other materials. Selected Timber Species: Glulam beams are commonly produced in New Zealand from the species Pinus Radiata and Douglas Fir. Occasionally species such as Macrocarpa and Lawson s Cyprus are also used. All of these species are suitable for structural glue laminated timber products. More exotic species can also be used with success. Species such as Jarrah, Cedar or Eucalyptus Saligna. Almost any timber species that can be kiln dried can be used in Glulam. However, be aware that different timber species will have varying characteristic strengths and the resulting Elastic Moduli of the Glulam will vary accordingly. Speak to a licensed Glulam manufacturer for more assistance on this subject. The clean lines and cranked shape of these pitched Glulam rafters illustrate the versatile roof forms possible using laminated timber. Page 5

6 SPECIFICATION DETAILS STRUCTURAL GRADES There are a range of structural grades of glue laminated timber beams produced in New Zealand in accordance with Standard AS/NZS These grades were developed by the Australian and New Zealand industries to assist designers and specifiers in the selection of Glulam members and their associated design properties. The following table of structural grade characteristics is referenced from AS/NZS 1328 part 2. Characteristic Strengths and Elastic Moduli for Glulam Grades Characteristic Strengths (MPa) Elastic Moduli (MPa) GL Grade Bending Tension parallel to grain Shear in Beam Compression parallel to grain Short modulus of elasticity parallel to the end grain Short duration modulus of rigidity for beams GL GL GL Note: All tables in this reference guide are based upon characteristics of Glulam meeting GL8 and GL10 grades. For references for higher grades than GL8 and GL10 as incorporated in these Span Tables please refer to a qualified producer. There is a list of qualified producers in the index at the back of this publication. Higher grades (i.e. GL12, etc) will give greater span and load carrying capability than GL8 and GL10 for the same section size. APPEARANCE GRADES There are three standard finishing grades that may be specified, as defined in AS/NZS 1328 part 1. The appearance grades relate to the aesthetic appearance of the visible surfaces of the glued laminated members. This classification bears no relationship to the structural performance of the timber. Definition of Appearance Grades Appearance Grade A Description This grade is intended for use in applications where appearance of the member is important and clear or painted finishes are used. All surface voids are filled or repaired. Unless it is specified otherwise, the surfaces shall be sanded to a minimum of 60-grit finish. B The grade is intended for use in painted applications where appearance is important but a planed finish is acceptable. The machining shall conform to No. 2 dressed surfaces grade as defined in AS Occasional skips in the surface are permissible and minor blemishes, voids and machining want shall be acceptable. The outer-most laminations shall be free of loose knots and voids. C This grade is intended for use in applications where appearance is not important. All blemishes and voids are acceptable. Note: The Appearance Grades most commonly produced in New Zealand are Grades A and B. Page 6

7 SPECIFICATION DETAILS SERVICE CLASSES The Service Class defines the environmental conditions in which glue laminated beams may be used. There are three service classes defined as shown in the following table. Definition of Environmental Conditions for Glulam Service Classes Service Class Description Environmental Conditions 1 Interior Service Class characterised by moisture content in the materials corresponding to a temperature of 20 C and relative humidity of the surrounding air only exceeding 65% for a few weeks per year. For example: Domestic Houses, Commercial Offices. 2 Exterior, under cover Service Class characterised by moisture content in the materials corresponding to a temperature of 20 C and relative humidity of the surrounding air only exceeding 85% for a few weeks per year. For example: Open sheds, exposed beams under soffits, porches, wool scouring plants, laundries. 3 Exterior, fully exposed Service Class characterised by climatic conditions leading to higher moisture content than Service Class 2, or where timber is directly exposed to sun and/or rain. For example: Marine structures, bridges. TIMBER TREATMENT SPECIFICATION OPTIONS In order to meet the Services Classes outlined above, depending on where the Glulam structure is to be used, specifiers will need to select timber treatment levels based on one of the following: Hazard Class H1 H2 H3 H4 H5 H6 End Use Low decay hazard Slight risk of decay and risk of termite attack Moderate decay hazard High decay hazard Severe decay hazard Marine hazard Timber treatment options can be either CCA treatment (the requirement for H5 or H6 is rare and specific situations should be discussed with the manufacturer) or LOSP (up to H3). LOSP is an envelope treatment, and because of this, care must be taken when cutting or drilling post-treatment that the affected area is recoated with a suitable protective coating. PAINTING PROCEDURE If Glulam has been pre-primed, the protective coating primer may tend to deteriorate over a period of time and become slightly chalky unable to bond adequately to any additional coating systems without some preparation work. A simple way of testing whether there has been any deterioration is to cut a small x through the existing coating system with a sharp blade. Press some cellulose sticky tape firmly across the cut and then rip off the tape. If any of the coating comes off with the tape then the primer is not adequately sound and must be removed by sanding. Sand back until the surface is completely free from all dirt and degraded material and dust off. Prime all surfaces, paying particular attention to cut ends and joints, with a good quality solventbased alkyd primer. Water based primers are less effective in this application. Allow to dry as per the manufacturers instructions and lightly sand to an even finish. Apply two coats of premium brand acrylic exterior grade top coat to the manufacturers recommendations. Page 7

8 ENGINEERING DESIGN PROPERTIES BEAMS FULLY RESTRAINED ON COMPRESSION FLANGE GL8 Glulam Grade = GL8 k1 = 0.8 SLS Deflection Limit = Span / 400 Section Size dxb (mm) Area A (mm 2 ) 135 x x x x x x x x x x x Section Moment of Modulus Z Inertia I V n Span (m) (10 3 mm 3 ) (10 6 mm 4 ) x x x x x x x x x (knm) - ULS, w (ULS) (kn/m) & w (SLS,k 2 =1.5) (kn/m) giving deflection = SLS Deflection Limit for Span (Note in both cases w is limited where necessary to prevent shear failure for the span) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) Page 8

9 ENGINEERING DESIGN PROPERTIES BEAMS FULLY RESTRAINED ON COMPRESSION FLANGE Continued GL8 Glulam Grade = GL8 k1 = 0.8 SLS Deflection Limit = Span / 400 Section Size dxb (mm) Area A (mm 2 ) Section Modulus Z (10 3 mm 3 ) Moment of Inertia I (10 6 mm 4 ) V n 135 x x x x x x x x x x x x x x x x x x x x Span (m) (knm) - ULS, w (ULS) (kn/m) & w (SLS,k 2 =1.5) (kn/m) giving deflection = SLS Deflection Limit for Span (Note in both cases w is limited where necessary to prevent shear failure for the span) w (ULS) 0.6 w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) Page 9

10 ENGINEERING DESIGN PROPERTIES BEAMS FULLY RESTRAINED ON COMPRESSION FLANGE GL10 Glulam Grade GL10 k = 0.8 SLS Deflection Limit = Span/ 400 Section Moment of!m (knm) - ULS, w (ULS) (kn/m) & w (SLS,k =1.5) (kn/m) giving deflection = SLS Deflection Limit for Span (Note in both cases w is limited where necessary to prevent shear failure for the span) Section Size Area A Modulus Z Inertia I Span (m) dxb (mm) (mm²) (10 mm³) (10 mm )!V !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) !M x w (ULS) w (SLS) Page 10

11 ENGINEERING DESIGN PROPERTIES BEAMS FULLY RESTRAINED ON COMPRESSION FLANGE GL10 Continued Section Size dxb (mm) Glulam Grade GL10 k = 0.8 SLS Deflection Limit = Span/ 400 Area A (mm²) Section Modulus Z (10 mm³) Moment of Inertia I (10 mm ) x x x x x x x x x x !V ( L ) ( L ) ( L ) ( L ) ( L ) ( L ) ( L ) ( L ) ( L ) ( L ) !M (knm) - ULS, w (ULS) (kn/m) & w (SLS,k =1.5) (kn/m) giving deflection = SLS Deflection Limit for Span (Note in both cases w is limited where necessary to prevent shear failure for the span) Span (m) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) !M w U S w (SLS) Page 11

12 ENGINEERING DESIGN PROPERTIES BEAMS FULLY RESTRAINED ALONG TENSION FLANGE GL8 Glulam Grade = GL8 k1 = 0.8 SLS Deflection Limit = Span / 400 Section Size dxb (mm) Area A (mm 2 ) 135 x x x x x x x x x x Section Modulus Z (10 3 mm 3 ) Moment of Inertia I (10 6 mm 4 ) V n x x x x x x x x x Span (m) (knm) - ULS, w (ULS) (kn/m) & w (SLS,k 2 =1.5) (kn/m) giving deflection = SLS Deflection Limit for Span w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) Page 12

13 ENGINEERING DESIGN PROPERTIES BEAMS FULLY RESTRAINED ALONG TENSION FLANGE Continued GL8 Glulam Grade = GL8 k1 = 0.8 SLS Deflection Limit = Span / 400 Section Size dxb (mm) Area A (mm 2 ) Section Modulus Z (10 3 mm 3 ) Moment of Inertia I (10 6 mm 4 ) V n 135 x x x x x x x x x x x x x x x x x x x Span (m) (knm) - ULS, w (ULS) (kn/m) & w (SLS,k 2 =1.5) (kn/m) giving deflection = SLS Deflection Limit for Span w (ULS) 0.6 w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) w (ULS) w (SLS) Page 13

14 ENGINEERING DESIGN PROPERTIES BEAMS FULLY RESTRAINED ALONG TENSION FLANGE GL10 Glulam Grade GL10 k = 0.8 SLS Deflection Limit = Span/ 400 Section Size dxb (mm) Area A (mm²) Section Modulus Z (10 mm³) Moment of Inertia I (10 mm ) 270 x x x x x x x x x x x x x x x x x x x x x x x x x x x x x !V Span (m)!m (knm) - ULS, w (ULS) (kn/m) & w (SLS,k =1.5) (kn/m) giving deflection = SLS Deflection Limit for Span (Note in both cases w is limited where necessary to prevent shear failure for the span) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) !M w (ULS) w (SLS) Page 14